As with capital goods (tangible items such as buildings, machinery, and equipment produced and used in the production of other goods and services), the consumption of a durable good is spread over its life span, which tends to create demand for a series of maintenance services.
The event which is referred to as The Phoenix Lights comprised of a series of incidents, involving a number of different craft and orbs which took place during the evening of March 13th 1997.
Lights of varying descriptions were seen by thousands of people between 19:30 and 22:30 MST, in a space of about 300 miles (480 km), from the Nevada line, through Phoenix, to the edge of Tucson.